Here is the full list of all 36 Trillion: God of Destruction achievements.
Watched everyone's hot springs event scenes!
Watched the true ending!
Executed Double-Up for the first time!
Used every Death Skill!
Affection Points have surpassed 1 billion!
Unlocked "Holy Illusion"!
Began a second playthrough!
Defeated Trillion with one of the first three Overlords!
Defeated Trillion in its Final Form!
Defeated Trillion in its Dragon Form!
Defeated Mokujin with one hit!
Strengthened a weapon by +30!
Strengthened a weapon by +10!
Gave someone the best present ever!
Reached the MAX level in a relationship!
Completed all entries in the Gift Guide!
Defeated Trillion in its Titan Form!
Broke through Trillion's outer armor!
Inflicted 10 billion damage with one hit!
Amassed a variety of Active Skills!
Amassed a variety of Passive Skills!
Got 100,000G!
Opened up all the Demon Seal slots!
Retreated for the first time!
Used Interact for the first time!
Used Order for the first time!
Gave a present for the first time!
Leveled up a skill to the max!
Executed Fever Time for the first time!
Trained for the first time!
Powered up a weapon or opened up a slot!
Performed a stat increase for the first time!
Challenged the Valley of Swords for the first time!
Obtained every trophy!
Watched all the lovey-dovey endings!
Cleared Challenge Mode!